Explosives disposal operations are inherently dangerous. Bomb technicians are more likely to be killed or injured while conducting an explosives disposal operation than any other mission, including attempting to render an improvised explosive device (bomb) inoperative.
Effective and efficient explosive disposals require a technician to safely deploy an explosives counter charge that maximizes the target surface area for a given net explosive weight (N.E.W.) of the explosives counter charge. The higher the N.E.W. of the explosives, the greater the risk of injury and collateral property damage. The greater the common surface area that the explosives counter charge has with the disposal target, the more likely the disposal target will be completely consumed. Efficient counter charge explosives must possess a sufficiently high detonation velocity in order to create a suitable cutting and thermal effect. These requirements are difficult to satisfy.
The general concept of using detonating cord to make an explosive matrix as an explosive counter charge is well known, as exemplified by U.S. Pat. Nos. 2,455,354; 3,242,862; 4,768,417; 5,437,230; and 6,182,553; and by the U.S. Navy's Distributed Explosives Technology, described in “Distributed Explosive Technology (DET) Mine Clearance System (MCS) Ex 10 Mod 0 Program Life Cycle Cost Estimate for Milestone III” (Jun. 4, 1999). These prior designs were created for large military applications. Such applications require significant manpower and financial resources. These prior art explosive matrices must be manufactured well in advance of their usage. Field assembly is not practical because they are a complex of multiple lengths of detonating cords joined together.
In addition, prior art explosive matrices are heavy and cumbersome to transport. They use rope or cord to hold the detonating cord together, creating undesirable bulk and weight.
Furthermore, detonating cord functions linearly. As a result, detonating cord can fail to propagate the detonation wave where the cord makes sharp turns, especially when large grain detonating cord is used. In some prior art designs, in order to assure sufficient transfer of the detonating wave between intersecting cords, clamps were used at all points of intersection of detonating cord. This adds further complexity and bulk to these prior art designs.
Moreover, use of low grain non-propagating detonating cord is not always possible in prior designs. Some prior art devices initiate at one point, in one direction, and use multiple lengths of detonating cord, which compromises reliability. Other prior art incorporates multiple initiation points and multiple lengths of detonating cord, again making the design more complex and the assembly more complicated and expensive.
In the past, the explosive charges used to counter individual explosives, such as roadside bombs, were point explosives. Generally, these devices were originally designed for some purpose other than explosives disposal, such as commercial blasting or military demolition. Many of these adapted designs are time consuming to construct and require large amounts of N.E.W. to be effective, resulting in greater risk of injury and unintended damage. Lastly, many of such explosives are costly and difficult to acquire.